Click-and-pop refers to the unwanted audio-band transients reproduced by a headphone when its amplifier is either enabled or disabled. This article looks at the cause of this annoyance and irritation, the tradeoffs in solutions. By eliminating the DC-blocking capacitors required at the output of traditional headphone amplifiers, technologies such as Maxim's patented DirectDrive remove click-and-pop noise while delivering better bass response and other benefits. This article by Long (Brandon) Xu, is a field application engineer, describes the DirectDrive approach, how it works, and the advantages it offers. The second half introduces a proven technique for removing click-and-pop from the headphones of cell phones and other portable devices.
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